Serpentine belt whine, and MT vs. AT tensioner pulleys.

[JFNash]

Since last fall I have noticed a loud whine when the engine is cold at about 2500-2800 rpm. Cranking the steering wheel at a stop changes the pitch of the noise. I isolated this to the serpentine belt by starting the car with the belt removed and since then have been dealing with more critical issues.

My first question is, does the steering/pitch change phenomenon definitively indicate a P/S pulley, or could an increased load on the P/S pump put more load on the tensioner/idler pulleys and cause a whine there to change pitch?

A secondary question is, although I have a manual transmission, my tensioner pulley is of the AT variety: http://www.eeuroparts.com/Main/PartDeta ... ?id=272136
rather than the MT variety:
http://www.eeuroparts.com/Main/PartDeta ... id=6842620

Also I have the AT tensioner design, here:
http://www.ipdusa.com/product.asp?P_ID=6244

I think this all may be due to the engine swap that the previous owner said he did on the car.

Is there any reason to have the MT pulley rather than the AT one? If so, should I buy the MT tensioner (different design) from IPD? I had planned to throw parts at it since I don't know where exactly the noise is coming from and this seems to be the most common part to cause this noise.

[precopster]

Why waste your money when you can just change the offending bearing? Like this:

https://www.matthewsvolvosite.com/forums ... 26#p170626

Of course before you even think about replacing or rebuilding it, remove it and spin the idler pulley on the tensioner assembly by hand. It shoud be quiet.

Also there is a plastic idler pulley which is separate from the tensioner. These often require replacement and can't be rebuilt.